Gas meter



May 5, 1942.

w.' L. BROWN GAS METER 3 Sheets-Sheet J.

Filed Feb. 19, 1940 Ema Patented May 5, 1942 UNITED STATES PATENT I OFFICE 24 Claims.

This invention relates to meters of different types, including gas meters of the positive displacement type. In the meter shown, the gas traverses a pair of opposing bellows, which, through offset flag rods, actuate a linkage mechanism whereby a tangent arm is rotated, said tangent arm being secured to a valve crank shaft from which slide valves are reciprocated to control admission of gas to and from the bellows.

My invention has for one of its aims to increase meter capacity without increasing the speed of the moving parts; and at the same time to minimize irregularities of meter movement to insure the delivery of gas with smaller fluctuations in outlet pressure than obtain in ordinary meters. These objects I realize, as hereinafter more fully disclosed, through improved proportioning and arrangement of the linkage mechanism and the slide valves driven thereby.

I further aim to increase the accuracy of meter registration over a considerable period of service, and to reduce gas leakage, by the provision of an improved stuffing box.

Another object is to increase the stiffness and strength of the offset flag rod by reinforcing the portions thereof most subjectto deflection, thus increasing the accuracy and smoothness of meter operation under varying conditions of service,

A further object of my invention is to attain the foregoing advantages in a meter which lends itself to very economical manufacture, from the standpoints both of the cost of the individual parts and of ready and easy assembly.

Other objects and attendant advantages will appear from the following detailed'description of the attached drawings, wherein Fig. 1 is a staggered horizontal section of a gas meter conveniently embodyin the present improvements, viewed from the top with certain parts broken out or removed to expose important, parts that would otherwise be hidden;

Fig. 2, a staggered longitudinal section of the meter viewed from the front, with certain parts broken out or removed;

Fig. 3, a front elevation of the index with the bottom portion broken out, in section as indicated by the arrows III-III of Fig. 1;

Fig. 4, a view from the top of a portion of the clutch mechanism of the index,,partly in section as indicated by the arrows IV-IV of Fig. 3;

Fig. 5, an elevation in section as indicated by the arrows V-V of Fig. 4, showing the parts in driving position for counterclockwise rotation;

Fig. 6, a like elevation showing the parts in driving position for clockwise rotation, and two intermediate positions;

Fig. 7, a front elevation of the dial of the meter index;

Fig. 8, a sectional elevation of the stufling box, with the corresponding shaft in place;

And Fig. 9, a plan view of a form of the offset flag rod alternative to the embodiment shown in Fig. 2.

The gas meter herein delineated for convenience of exemplifying'my invention is generally of well known construction, having a generally rectangular casing 50, with a horizontal partition (valve table) 5| (Fig. 2) setting apart a comparatively high lower compartment 52 and a shallower upper compartment 53. The lower compartment 52 is in turn subdivided by a central longitudinal partition (not shown) into two chambers for the two bellows 54 of the meter. Leading from the gas inlet 55 is a channel 56, in this instance above the valve table 5|, by which the gas is conducted to a box 51 (Fig. 1) containing the valves 58 whereby admission of gas to and from both sides of the bellows is controlled. Gas may be conducted from the inlet 55 to the valves 58 otherwise than herein shown by way of example, without affecting the advantages of my invention. Each of the valves 58 comprises a cover 58 which moves back and forth over a seat 68 to connect the outer ports 6| and 62 alternately with the center port 63. The diaphragm ports 62 communicate respectively with the inside of the bellows 54 through channels as instanced by dotted lines at 64 in Fig. 2; while the case ports 6| communicate respectively with the outsides of the bellows. The center ports 63 lead into the branches 65 of a fork channel 66 by which gas is conducted to the outlet 61 of the meter.

As shown, each bellows 54 carries a disc 68 (Fig. 2), whereon are mounted brackets 69, 10, in which the offset vertical portion ll of the flag rod turns freely. Collars l2, 13, fast to offset portion 1|, position the disc 68 as to height above the meter bottom. A disc guidewire l4, sliding in disc guides 15, 16, which are fast to disc 68, insures that the various positions of the disc during its travel shall be substantially parallel to each other, said guide wire being journalled in bearings ll, 18, fixed to the meter bottom. The offset vertical portion H is joined by transverse extensions to vertical portions of the flag rod 19 and 80, journalled respectively in the gas tight flag-stufiing box BI, and in the flag rod bearing 82. Between the portions 19 and 88, and fixed thereto, extends a substantially vertical portion 83, for stiffening the structure. This offset flag rod combines the functions of the flag rod, flag, and rock shaft of ordinary meters.

Affixed to the upper ends of the portions 19 of the flag rods are flag arms 84, 85, which, through links 86, 81, are connected to the tangent post 88 on the tangent arm 89. The bulge 90 in the rear meter casing wall (Fig. 1) provides room for the movement of the rear flag arm 84. The tangent post 88 is adjustable along the threaded portion of the tangent arm 69, and is fixable in adjusted position by jam nuts as usual, The tangent arm 89 is adjustably fixed to the valve crank shaft 9|, which is journalled near its upper end in the kingpost 92, and also in the gas tight crank stuffing box 93 (Fig. 2). The covers 59 of the valves 58 are reciprocated on the valve seats 69 by means of crank arms 99, 95, actuated by the crank member 96, which crank member is fast to the valve crank shaft 9|. The valve covers 59 are confined to straight line motion by valve guide wires '91 engaging valve guides 96, room for motion being.

afforded by bulges H35. Worm 99, fast to valve crank shaft 91, drives an axle wheel Hill .on axle NH. The axle at one end is journalled in an axle bearinglliz (Fig. 1), and at the other end is connected to the mechanism of the index, generally indicated at 193.

The refinements which I have made for the attainment of the important practical advantages hereinbefore pointed out are as follows:

The moving parts are proportioned and arranged (with exceptions to be noted later) generally as described in my co-pending application 291,843 filed Aug. 25, 1939, so as to bring the flag arms 89, 85 to the ends of their strokes when the valve covers 59 are at or very close to the corresponding points of admission, valve covers being set to give full opening of ports GI, 62 without wipeover. For this result, the angle I94 (which is the angle between crank arm 94 when valve cover 59 is in admission position, and the axis of valve cover motion 915) is equal, or very nearly equal, to the angle 10'! (which is the angle between lines drawn from the extreme positions of the bearing axis of the rear flag arm 84, to the axis of valve crank shaft 9 l The corresponding angle in respect to front flag arm 65 is also equal, or very nearly equal, to angle I94. This arrangement necessitates flag arm links 96 and 81 of different lengths.

Differing from my application 291,843, however, the present invention shifts the flag rods and; valve crank shaft towards the inlet 55 of the meter, thus increasing the effective flag length, and decreasing the angle of sweep .of the fiag arms 84 and 85 for a given stroke of the disc 68. Thus the disc stroke is considerably increased without unduly increasing the angularity between the links 86, 81 and the tangent I arm 89. This is important, because a considerable increase of such angularity increases the irregularity of meter operation, and also increases wear at the bearings.- The lengthening of the disc stroke increases the volume .of gas delivered per revolution of the meter; by which either increased meter capacity for a given size of meter, or slower speed at a given delivery per hour, or both together, may be secured.

A further difference from my application 291,843 is that the axes of valve cover motion are set at an acute angle, with a separate crank for driving each valve cover, instead of the usual arrangement, employed in the application mentioned, in which a single crank drives both. valve covers, with axes at right angles. The present construction permits the valves to be positioned close to the outlet, thus avoiding interference between the fork channel branches 65 and the bellows 1 (or an increase of the height of compartment 52 to eliminate such interference) and permitting the use of a shorter fork channel 66. It will be seen that if the valve axes, passing through the valve crank shaft axis, were disposed at right angles as usual, the valves would have to be set further from the outlet 61, with the disadvantages mentioned. The upper crank bearing I98 (Fig. 2) is made smaller than the lower crank bearing I99, so that the lower crank arm may be slipped over the upper crank bearing in assembling.

To secure the increased disc stroke contemplated, a collapsible form of bellows, such as shown in my co-pending application 238,133 filed Nov. 1, 1938, may be used, or any of several well known designs. Since the bellows employed forms no part of my present invention, it is not further detailed.

Referring now to my improved index:

If an ordinary meter is connected in reverse by a fraudulentconsumer, and the commodity under supply passed through the meter in the reverse direction, entering at the meter outlet and coming out at the meter inlet, then the index movement will likewise be reversed, and the index reading will be decreased by the passage of the commodity, instead of being increased. To guard against this practice, reverse stop means have been commonly provided, so as to stop the reverse motion of the meter after a relatively small movement.

Such reverse stop devices as applied to gas meters are instanced in United States Patents 1,187,966 and 1,196,653, granted to me respectively on June 20, 1916 and Aug. 29, 1916. When a meter equipped with such a reverse stop device is connected in reverse, and gas passed through it, the meter moves backwards until further motion is prevented by the action of the stop device. Under this condition, if the pressure in the gas supply main is sufficient to raise the valve covers from their seats against the resistance of gravity and the adhesion between valve cover and seat due to gas condensation, a certain amount of gas will be delivered to the consumers appliances without registering on the meter index. On the other hand, if the weight of the valve covers and the adhesion due to condensation are enough to hold them on their seats, then such strain may be brought on the movable parts of the meter as to deform permanently, or even break or loosen, some part thereof, thus affecting meter accuracy or preventing normal operation.

It is conceivable that, with certain relations 'of pressure in the main, weight of valve covers, and adhesion due to condensation, both these undesirable conditions may occur in the same meter, namely, fraudulent procurement of gas, and damage to the meter mechanism.

Therefore, as the reverse stop devices of the prior art do not in all cases prevent theft of gas by reversing the meter, and may by their action damage the meter mechanism, it is of advantage to omit the reverse stop device altogether, and to guard against theft through a reversed meter by providing an index that will register the passage of ga positively without regard to the direction of flow.

This has been accomplished in my invention, in which a proving head shaft Hi], journalled in frame plates Ill and H2 (Fig. 4), is rotated by the meter mechanism in the usual manner by means of the axle lfll. Fast to this shaft H9 is an element H3 carrying a clutch device, this element in the embodiment shown taking the form of a gear wheel, and journalled in this element I I3 is a clutch device, here exemplified as a double-ended, self-reversing, pivoted pawl H4, having one end H5 disposed on one side of element H3, and the other end H6 on the other side. A clutch-driven member I I I, in the present embodiment being a disc with pins I I8 fast thereto, with a gear wheel H9 fast to said member, is journalled on proving head shaft I I0, both member H1 and gear wheel H9 being loose on shaft H0. On the other side of element H3, another clutch-driven member I20, provided with pins I2I in the present embodiment, with a gear wheel I22 fast to said member, i journalled on proving head shaft I I0, both member I20 and gear wheel I22 being loose on shaft H0.

The gear wheel H9 drives a gear wheel I23 (Figs. 1 and. 3), and the gear wheel I22, through an intermediary I25, drives a gear wheel I24; and both these gear wheels I23 and I24 are fast to a secondary shaft I26, in the form of a pinion, journalled in frame plates III and H2 (Fig. 1), which secondary shaft drives the register shafts I21, I28, I29, and I30 (Fig. 7) through reduction gearing. In the size of meter chosen for illustration, the proving head shaft H may be arranged to revolve once for the passage of 2 cubic feet of gas through the meter, and the shafts I21, I28, I29, and I30 for the passage of 1,000, 10,000, 100,000, and 1,000,000 cubic feet respectively; and the reduction gearing arranged to correspond.

Normal direction of the proving head shaft H0, observed from the front of the meter, is

counter clockwise rotation, and with this motion the element H3 will drive the member HI directly by means of the pawl H4, one end H engaging one of the pins H8, and the other end I I6 being in contact with the proving head shaft H0 (Figs. 4 and 5). The secondary shaft I26 will then be driven clockwise, and the passage of gas registered on the index. Meanwhile the gear wheel I22 will be driven by the gear wheel I 24, through the intermediary I 25, in an idling motion, pins I2I on member I20 (which member is fast to gear wheel I22) being clear of the pawl H4.

When the direction of the proving head shaft H0 is reversed to clockwise, as by reverse connection of the meter for the purpose of stealing gas, the pawl I I4 will be moved backward without causing any rotation of the register shafts I21, etc., until after the end H5 of the pawl H4 strikes the pin H8 adjacent to the pin by which the pawl has been driving the index, as in the full line representation of the pawl in Fig, 6. When and H5 strikes the pin in backward movement, this will turn the other end H6 into position to engage one of the pins I2I on the other member I20; and, when end II 5 has engaged the proving head shaft II 0 (as in dash-anddot lines at I3I in Fig. 6), the member I20 will be driven in a reverse, or clockwise, direction. An intermediate position of the pawl I I 4 is shown at I32.

The secondary shaft I26, (Fig. 3) however, and the rest of the registering mechanism of the index, will now be driven in the same directions as those in which they moved when driven by member H'I under counterclockwise rotation of proving head shaft H0, on account of the intermediary wheel I25, which reverses the direction of motion transmitted from the gear wheel I22 as compared to the direct drive from gear wheel H9; so that reverse motion of the meter will be registered on the index as if the meter were moving in the normal direction.

While member I20 is driving the index as outlined in the two foregoing paragraphs, the gear wheel H9 and the member I I! will be driven in an idling motion, with none of the pins H8 in contact with the pawl H4. Thus as long as the meter runs backwards, the index reading will be added to just as if the meter were operating normally.

When the proving head shaft resumes normal rotation, as when the meter is re-set in proper position, the pawl H4 will shift to engage one of the pins H8 on member H1, and the index will be driven in the normal manner.

Thus a selective clutch device is provided, by which the pawl I I4 drives directly one member, H1, when the-proving head shaft H0 rotates in the normal direction, with no contact meanwhile between the pawl and the other member I20; while in reverse motion of the proving head shaft, the pawl drives directly member I20 and is not in contact with member III. Normal rotation of member H1 and reverse rotation of member I20 are both translated into the same direction of rotation in the register shafts of the index, as already explained.

If it is desired to include in the index an extra proving head shaft I33 (Figs. 3 and'7), revolving at a higher speed than the main proving head shaft H0 (as in most ordinary meters) such shaft I33 is driven by a gear wheel I34 fast thereto, through the intermediary I35, by the element I I3, made in the form of a gear wheel as shown.

The bearing I36 in the element I I3 (Figs. 4, 5) is made with a bore sensibly larger in diameter than the pawl H4, to present as little resistance as possible to the turning of the pawl, and to facilitate assembly.

It should be noted that the proving head shaft H0 is driven directly by the axle II, as in the ordinary meter, and the extra proving head shaft I33 is driven from the proving head shaft; so that my construction does not increase the lost motion of the shafts referred to, as compared to ordinary index design. This is important because of the use made of these shafts in proving and testing the meter withthe top cover in place.

One of the objects of certain reverse stop devices of the prior art, as in my Patents 1,187,966 and 1,196,653 already mentioned, was to allow a certain minimum backward motion before the stop was applied. In normal operation, when the consumers appliances are all shut off after a period of use, the corresponding distribution piping is filled with gas at about the temperature of the underground street main. This gas when at rest would rise in temperature, as the atmosphere around the piping is usually warmer than the street main, and this rise in temperature would expand the gas and force a portion of it backwards through the meter and into the main. The reverse stop devices referred to were designed to allow sufficient backward motion of the meter, before the stop was applied, to equalize the excess pressure due to the higher temperature in the piping, thus preventing damage to the meter mechanism.

It will be seen that my invention will take care of such reverse rotation of the meter in normal service, in any amount; but it should be noted that the backward travel of the proving head shaft H0, from the time that the pawl end H5 leaves the pin II-8 it has been driving to the time it contacts the adjacent pin in backward rotation, corresponds to about two complete revolutions of the valve crank shaft 9I, in the size chosen for illustration. This amount of movement will usually be more than enough to relieve the excess pressure in the piping when the meter comes to rest. When the meter again moves forward, after gas is turned on in an appliance, the pawl end H5 will be carried forward and resume its function of driving the member III.

In the illustrations shown, the ratio between the gear wheels I22 and I24 is the same as the ratio between the gear wheels H9 and I23 (Fig. 3). If desired, however, and if local regulations permit, the ratio between gear wheels I22 and I24, which wheels drive the index in reverse rotation of the meter, may differ from the ratio between gear wheels H9 and I23, to penalize the fraudulent consumer by registering more on the index in reverse rotation of the meter, for a given quantity of gas, than would be registered in normal meter operation.

An improved stufling box is provided, especially for use as the crank stuiflng box 93, although it may also be used for the flag stufiing boxes 8|. In the ordinary meter, stuffing boxes are made gas tight with yarn, felt, or similar packing under pressure, and the Wear which takes place after a comparatively short period of service is frequently enough to cause the meter to run fast, because such Wear lessens the resistance to meter movement. Under longer service, of course, a leak develops. The stufiing box shown in Fig. 8 will, in long continued service, maintain more closely the frictional resistance existing at the calibration of the meter, remain tighter under wear, and provide a journalling for the valve crank shaft 9| keeping it closer to its original alignment, than the construction employed in the ordinary meter.

In Fig. 8, taken as applied to the crank stufi'ing box 93, the valve crank shaft 9! carries fast to it a sealing member I31, fashioned from a ball of appropriate composition and hardness, as of bronze or Monel metal, such balls being commercially available with very small limits of accuracy. The sealing member I3! is seated at the bottom of the stufiing box body I38 so as to form a gas tight joint. The bearing surface of the stuffing box body in contact with the sealing member I31 may be finished by pressure or impact from a hardened ball of nearly the same diameter as the ball from which the sealing member I31 was made, or by contact with such a ball rotating on a spindle. A small ball bearing assembly I39, preferably of a type already in commercial production, contacts sealing member I31 from above, and pressure downwards is exerted by a plate spring I49 above the ball bearing assembly I39. The tension of spring I49, and consequently the sealing pressure, is adjusted by turning the threaded stuffing box cap I. Grease may be introduced into the hollow stuffing box body I38 before complete assembly, and after screwing down the cap I4I, a further supply of grease may be deposited in the depression I42. The crank member 96 (Fig. 2) is integrally distinct from valve crank shaft 9!, but fastened thereto after said shaft is in place in the stumng box.

The links 86, 87 (Fig. 1) act as thrust rods over about half their travel. For proper stiffness, therefore, with a given cross sectional area, the moments of inertia about horizontal and vertical axes should be equal. This condition I meet by providing links of symmetrical cross section, preferably round or square, as compared to the links of oblong section of the prior art. These links may be of tinned steel wire. To give proper bearing surfaces, bushings of appropriate composition and hardness are set in the ends of the links, and fastened by solder or otherwise. Increased bearing surface may be provided at small extra expense by increasing the vertical height of these bushings.

In accordance with my invention, the offset flag rod shown in Fig. 2 is made from two opposingly arranged U shaped components, one component having aligned trunnion portions I9 and 8t, and transverse extensions between the oifset vertical portion II and the two trunnion portions; and the other component having the substantially vertical portion 33, and transverse extensions parallel to those of the first component and extending in lapping relation nearly or quite the full length thereof, ending as at I43 and I44. These parallel transverse portions of the components of the flag rod are welded or otherwise joined together. By thus increasing the depth of the transverse portion in the direction in which the pressure of the disc 88 is transmitted, the stiffness of the Whole system is markedly increased. This is important because when disc travel varies under different conditions of service, due to varying deflections in the offset flag rod, the accuracy of the meter is correspondingly affected.

Fig. 9 shows an alternative form of my improved offset flag rod, in which one component I45 is substantially vertical, corresponding to portions I9, 83, and 89 of Fig. 2; while the other component has a vertical portion I46 (corresponding to 'II of Fig. 2) and also two retroverted transverse portions embracing component I45, as in I41 and I48, welded or otherwise fastened to vertical component I45, and to each other along their length. This construction also gives the increased depth of transverse portions described in reference to Fig. 2.

While I have herein shown and described my invention in connection with a gas meter of a specific type, certain of the features can obviously be embodied in other types of meters within the scope of the appended claims.

Having thus described my invention, I claim:

1. In a gas meter, an offset flag rod consisting of two generally U shaped components, the legs of the said U shaped components being respectively in lapping relation to each other and fastened together, so as to form two transverse portions connecting two substantially vertical portions of the flag rod.

2. In a gas meter, an offset flag rod consisting of two components, one substantially vertical, and the other substantially U shaped, the U shaped component including a vertical portion connected by two transverse portions to the other component; the transverse portions being double.

3. In a gas meter, a pair of bellows; valves, comprising slide covers and seats for controlling flow of gas into and out of the bellows; mechanism deriving movement from the bellows for actuating the valves including a valve crank shaft with plural cranks, a tangent arm on the shaft, front and rear flag rods, front and rear flag arms on the rods connected by front and rear links to the tangent arm, and crank arms connecting the valve crank shaft with the valves, such that a line drawn from one extreme position of a flag arm bearing axis to the valve crank shaft axis forms an acute angle with a line drawn from the other extreme position of the same flag arm bearing axis to the valve crank shaft axis, said acute angle being substantially equal to the angles between a crank arm and the corresponding axis of valve cover motion when the valve cover is in admission positions.

4. A gas meter as in claim 3, in which the arcs of motion of the flag arm bearing axes included within said acute angles are respectively concave and convex when viewed from the position of the valve crank shaft.

5. A gas meter as in claim 3, in which the positions assumed by the flag arms during their travel are generally transverse to the meter for one flag arm, and generally lengthwise of the meter for the other flag arm.

6. A gas meter as in claim 3, in which the crank-shaft is on one side of the bellows axis and the flag rods are further remote from the bellows axis than the valve crank shaft, and on the same side of said axis as said shaft.

7. A gas meter as in claim 3, in which the axes of valve cover motion are in acute angular relation.

8. A gas meter as in claim 3, in which the cranks are of different diameters to facilitate assembly of the crank arms.

9. In a gas meter, a pair of bellows; valves, comprising slide covers and seats for controlling flow of gas into and out of the bellows; mechanism deriving movement from the bellows for actuating the valves, including a valve crank shaft with plural cranks, a tangent arm on the shaft, front and rear flag rods both on the same side of the bellows axis, front and rear flag arms on the rods connected to the tangent arm by front and rear links, and crank arms connecting the valve crank shaft with the valves, such that a line drawn from one extreme position of a flag arm bearing axis to the valve crank shaft axis forms an acute angle with a line drawn from the other extreme position of the same flag arm bearing axis to the valve crank shaft axis, and such that the arcs of motion of the flag arm bearing axes included within said acute angles are respectively concave and convex when viewed from the position of the valve crank shaft, whereby synchronism in the movements of bellows and valves is produced.

10. A gas meter as in claim 9, in which said acute angle is substantially equal to the angles between a crank arm and the corresponding axis of valve cover motion when the valve cover is in admission positions.

11. A gas meter as in claim 9, in which the front and rear links are of different lengths.

12. A gas meter as in claim 9, in which the positions assumed by the flag arms during their travel are generally transverse to the meter for one flag arm, and generally lengthwise of the meter for the other flag arm.

13. A gas meter as in claim 9, in which the axes of valve cover motion are in acute angular relation.

14. A gas meter as in claim 9, in which the cranks are of different diameters to facilitate assembly of the crank arms.

15. In a gas meter, a pair of bellows; valves, comprising slide covers and seats for controlling flow of gas into and out of the bellows; mech-- anism deriving movement from the bellows for actuating the valves, including a valve crank shaft with plural cranks, a tangent arm on the shaft, front and rear flag rods, front and rear flag arms on the rods connected to the tangent arm by front and rear links of different lengths, and crank arms connecting the valve crank shaft with the valves, such that a line drawn from one extreme position of a flag arm bearing axis to the valve crank shaft axis forms an acute angle with a line drawn from the other extreme position of the same flag arm bearing aXis to the valve crank shaft axis, said acute angle being substantially equal to the angles between a crank arm and the corresponding axis of valve cover motion when the valve cover is in admission positions.

16. A gas meter as in claim 15, in which the arcs of motion of the flag arm bearing axes included within said acute angle are respectively concave and convex when viewed from the position of the valve crank shaft.

17. A gas meter as in claim 15, in which the positions assumed by the flag arms during their travel are genreally transverse to the meter for one flag arm, and generally lengthwise of the meter for the other flag arm.

18. A gas meter as in claim 15, in which the axes of valve cover motion are in acute angular relation.

19. A gas meter as in claim 15, in which the cranks are of different diameters to facilitate assembly of the crank arms.

20. In a gas meter, a pair of bellows; slide valves for controlling flow of gas into and out of the bellows; mechanism deriving movement from the bellows for actuating the valves, including a shaft; a sealing member having a spherical surface fast to said shaft; a stuffing box body for said shaft providing a seat for the sealing member; a ball bearing assembly including balls which engage the surface of the sealing member from above; a plate spring imposing pressure upon the ball bearing assembly; and a threaded cap for the stuffing box by which pressure imposed upon the ball bearing assembly may be adjusted.

21. A gas meter as in claim 20, in which a grease accommodating space is provided within the stuffing box above the sealing member and around the ball bearing assembly.

22. In a gas meter, a pair of bellows; slide valves for controlling flow of gas into and out of the bellows; mechanism deriving movement from the bellows for actuating the valves, including a valve crank shaft; a crank member, separate from the valve crank shaft but fast thereto; crank arms connecting the crank member with the valves; a sealing member having a spherical surface fast to said valve crank shaft; a stufling box body for said valve crank shaft providing a seat for the sealing member; a ball bearing assembly including balls which engage the surface of the sealing member from above; a plate spring imposing pressure upon the ball bearing assembly; and a threaded cap for the stuffing box by which the pressure imposed upon the ball bearing assembly may be adjusted.

23. A gas meter as in claim 22, in which the space within the stuffing box above the sealing member and around the ball bearing assembly and plate spring is filled with grease.

24. In a gas meter, a flag rod comprisin two components, one of said components being U shaped, the legs of said U shaped component being fixed to the other component, one of said components having transverse extensions overlapping and fixed to said legs of the U shaped component.

WILLIAM LAIRD BROWN. 

